Apparatuses for transforming plastic preforms into plastic containers have been known for some time from the prior art. Usually, in a plurality of blow moulding stations, plastic preforms are transformed into plastic containers as a result of being acted upon by compressed air. During the expansion process, a number of movement processes take place alongside one another. For instance, usually the blow mould carrier halves are unfolded from one another in order to introduce a plastic preform and then are folded together in order to be able to carry out the expansion process. At the end of the expansion process, the blow mould carrier parts are unfolded from one another again in order thus to be able to remove the finished, blow-moulded plastic container. In the closed state of the blow mould carrier parts, particularly during the expansion process, the blow mould carrier parts are additionally locked to one another in order thus to be able to withstand the not inconsiderable pressures.
Also known from the prior art are sterile applications in which the individual blow moulding stations are guided inside a clean chamber. For example, there is described in WO 2010/020529 A2 an apparatus for transforming plastic preforms into plastic containers, having a transport device, which comprises a plurality of blow moulding stations, and a clean chamber.
By means of the clean chamber, aseptic conditions can be ensured during the production of the plastic containers and also during the filling thereof with beverages.
The subject matter of WO 2010/020529 A2 is hereby fully incorporated by way of reference in the subject matter of the present disclosure.
In some countries, guidelines are set for such aseptic treatments. In the USA, for example, such guidelines are set and monitored by the FDA (Food and Drug Administration).
As mentioned above, one important component of a blow moulding station is in each case the lock mechanism which connects or locks the two mould carrier halves to one another during the blow moulding process. At the end of the blow moulding process, the lock opens. Once the mould has opened, the bottle can be removed and a new preform can be introduced. In the prior art, this lock mechanism usually comprises a lock shaft which is mounted in one of the two mould carriers. A plurality of bearing points distributed along the height of the mould carrier ensure a uniform distribution of force in the components. This is important since the lock has to absorb a retaining force of several 10 000 N. The locking process consists for example of a rotational or linear movement of the lock. This movement is usually generated by a stationary cam fixed to the basic structure of the machine and is transmitted to the lock shaft via various deflections.
The opening and closing movement of the mould carrier is controlled independently and separately from this. Since in the prior art the two mould carrier halves are opened by the same angle, they are mechanically connected via various levers and deflections. Actuation takes place via a cam. Two cams are therefore required for the actuation as a whole, one for controlling the two mould carrier halves and one for controlling the lock.
It may therefore be desirable to simplify the actuation mechanism for such blow moulding machines.